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Ton of rain today + debris

We've had a lot of rain this month and my fc and cc levels have been good. Since my cpsc48 went out, I'm back to bleach, and a bottle of 8.25% a day keeps it between 3 and 7 with a cya of 70.

Today's rain was heavy, pool is to the rim, and a ton of dead grass clippings got into the pool and turned it cloudy. I can see the bottom of the shallow end, but not the deep end.
I came home to find it and put in 2 6% 121oz bottles and a little bit of 8.25% which brought my level from 3 to 10.5ppm

2 hours later it came down to 9.5 and cc levels are still 0.5 or less.

Went bottle shopping after depleting my stash, calculated I needed 3.5 bottles to bring it up to 20ppm shock level. I put in 4 bottles and measured 22ppm after an hour and will retest in the morning.

Re: Ton of rain today + debris

I hate to be the bearer of bad news, but the bright side is, there's a silver lining to this cloud.
Unfortunately you became susceptible to, and ultimately the victim of algae growth as a result of maintaining too low an FC for your CYA.
The minimum FC for bleach/LCL as a CL source at a CYA of 70ppm is 5ppm FC, not 3.
At that low an FC, there simply wasn't enough chlorine to keep the organics at bay to prevent algae growth.

I presume the mix up happened when you switched from your SWCG as the pool's CL source to bleach/LCL. SWCGs produce pure HOCl, the active sanitizing agent in bleach/LCL. It's stronger and more potent in sanitizing power per ppm than bleach/LCL. So at the recommended CYA levels for SWCG chlorinated pools, you run at a lower ppm FC.
Which just so happens to be 3ppm, what you were dosing to with bleach/LCL.

So I can see where the mixup so easily happened. It can be confusing, but live and learn, right?
Now you'll be armed for the future though.

Also, having caught it so early, you've got a major leg up on it!
As it doesn't look that bad, usually about how a green swamp looks mere days before the finish line, a week or more into SLAMing. I wouldn't be surprised if your SLAM operation goes preeeetty quickly!
I'd say that's pretty cool news as well.

Re: Ton of rain today + debris

Originally Posted by y_not

... SWCGs produce pure HOCl, the active sanitizing agent in bleach/LCL. It's stronger and more potent in sanitizing power per ppm than bleach/LCL. So at the recommended CYA levels for SWCG chlorinated pools, you run at a lower ppm FC....

You are saying that 3ppm (or 10, pick any number) free chlorine from bleach, as measured by our TF-100 kits, has a different effect than 3ppm of free chlorine made by a saltwater chlorine generator. I don't understand how that's possible.

Would that mean that the algae killing power of 10ppm FC from cal hypo is different from the algae killing power of 10ppm FC from trichlor or bleach?

Re: Ton of rain today + debris

With the pool level that high, isn't that negating the effect of your skimmer? Mine won't pull surface debris if the water level is too high. I would backflush or pump to waste to get to where the skimmer works again.

Re: Ton of rain today + debris

Had my wife put 2 121oz bottles of 8.25% in at noon, came home and it measured 18. My son vacuumed and backwashed for me this evening, and about 10pm it was at 16. put in 4 bottles to raise it to 28. CC almost zero, barely any pink tint at all with 5 drops in 10ml sample.

With my high powered Brinkman LED spotlight, I can just start to see the bottom of the deep end already. It's no longer a greenish tint, but more of a white cloud.

Re: Ton of rain today + debris

Originally Posted by CUTiger78

Originally Posted by y_not

... SWCGs produce pure HOCl, the active sanitizing agent in bleach/LCL. It's stronger and more potent in sanitizing power per ppm than bleach/LCL. So at the recommended CYA levels for SWCG chlorinated pools, you run at a lower ppm FC....

You are saying that 3ppm (or 10, pick any number) free chlorine from bleach, as measured by our TF-100 kits, has a different effect than 3ppm of free chlorine made by a saltwater chlorine generator. I don't understand how that's possible.

Would that mean that the algae killing power of 10ppm FC from cal hypo is different from the algae killing power of 10ppm FC from trichlor or bleach?

I'm a little confused.

No ... a ppm is a ppm.
The SWG can be run at lower FC levels due to a few reasons, the biggest is the harsh environment within the cell.